紫外光活化亚硫酸盐降解水中卡马西平

研究了紫外光活化亚硫酸盐高级氧化工艺降解水中典型新污染物——卡马西平（CBZ）的效能和降解机制.探究了不同溶解氧浓度[ρ（DO）]对紫外光活化亚硫酸盐降解CBZ的影响,并在模拟自然水体环境控制初始ρ（DO）为（8.0±0.2） mg·L^-1条件下,考察了不同工艺参数（亚硫酸盐投加量、反应pH）与水环境要素（碳酸氢根离子、氯离子、腐殖酸）对CBZ降解效能的影响.结果表明,紫外光活化亚硫酸盐工艺可在30 min内降解85.3%的CBZ,降解过程遵循拟一级动力学,动力学常数为0.055 7 min^-1.并采用电子顺磁共振波谱技术、活性物质淬灭实验和竞争反应动力学实验发现,CBZ的降解主要来自紫外光活化亚硫酸盐工艺中硫酸根自由基（SO₄^-·）与羟基自由基（·OH）等活性物质,且降解贡献率分别为43.9%和56.1%.而且CBZ降解率随HCO₃^-浓度升高而降低,但Cl^-浓度变化对CBZ降解率影响不大,水中存在的腐殖酸可显著抑制CBZ的降解.反应过程中硫酸盐的积累量显著低于《生活饮用水卫生标准》（GB 5749-2022）限值,且亚硫酸盐消耗速率（0.004 4 min^-1）显著低于CBZ的降解速率,说明亚硫酸盐可被紫外光高效活化用于降解水中存在的CBZ.     

Germline mosaicism complicates molecular diagnosis of Lesch–Nyhan syndrome

A healthy female with a brother suffering from Lesch–Nyhan syndrome was assigned a carrier status on the basis of haplotype analysis employing flanking and intragenic polymorphic markers of the HPRT gene. Her mother has been confirmed as a definite carrier by cell growth selection studies in cultured fibroblasts. In our proposita's first pregnancy, a male fetus was identified carrying the risk allele. Afterwards, the underlying novel mutation A161E (GCA→GAA at position c482) could be identified in the affected brother and in the heterozygous mother but not in the DNA of the pregnant sister and fetus. The fetus was also confirmed to be normal by uptake of 14C-hypoxanthine in cultured amniotic cells. To test the discrepancy, the investigation was extended by recruiting additional family members. The data obtained showed that the mother had passed her risk haplotype to the affected son as well as to her mutation-carrying and non–mutation-carrying daughters. This provides the first evidence of concomitant somatic and germline mosaicism in Lesch–Nyhan syndrome. The study has a bearing on genetic counselling and cautions against the reliability of only using indirect genetic diagnosis even with intragenic markers. Copyright © 2004 John Wiley & Sons, Ltd.     

Isolated sulfite oxidase deficiency: mutation analysis and DNA-based prenatal diagnosis

Isolated sulfite oxidase deficiency is an autosomal recessive, neurological disorder resulting from a defect in SUOX, the gene encoding the enzyme that catalyzes the terminal reaction in the sulfur amino acid degradation pathway. In its classical, severe form, sulfite oxidase deficiency leads to intractable seizures, severe and progressive brain pathology and death at an early age. We report here on clinical features and mutational analysis of the genetic defect in a newborn with sulfite oxidase deficiency. Cultured fibroblasts from this patient exhibited no detectable sulfite oxidase activity, and a unique four base pair deletion was present in the cDNA isolated from the same source. Identification of the same genetic defect in a heterozygous state in each of the parents and the monitoring of subsequent pregnancies in this family by DNA-based prenatal diagnosis are also described. The deletion mutation was identified in a homozygous state in uncultured chorionic villus tissue from the second pregnancy that was subsequently terminated. In the third pregnancy, the presence of sulfite oxidase activity and identification of the mutation in a heterozygous state suggested that the fetus was not affected. This pregnancy resulted in the birth of a normal child. Copyright © 2002 John Wiley & Sons, Ltd.     

基于突变理论的油库火灾爆炸分析与模糊动态评价

通过对目前油库常用评价方法的分析,这些方法存在的缺点主要是评价中参数值的选取、各评价指标权重的确定以及评价因素重要性的确定等问题,因易受到参评人员主观的影响,而导致评价难以获得客观结果。笔者提出了基于突变理论的模糊动态评价方法。介绍了突变理论的基本原理;建立油库火灾爆炸尖点突变模型,并对油库火灾爆炸现象进行突变分析;重点研究基于突变理论的油库模糊动态评价的基本思想和方法,通过对评价目标进行多层次分解,根据突变论归一公式进行量化递归运算,分别计算出不同时期油库安全总突变隶属函数值,从而实现对油库安全状态的模糊动态分析与评判。该方法的优点就在于各指标的重要性及其量化是根据突变论中归一公式本身的内在机理决定的,既避免了评价指标权重的确定问题,又减少了评价人员主观因素的影响。因而,评价结果客观、准确。示例表明,该方法是合理可行的。     

Prenatal diagnosis of Niemann–Pick diseases types A,B and C

Prenatal diagnosis of Niemann–Pick disease types A and B is routinely accomplished by sphingomyelinase assay. For Niemann–Pick type C disease, demonstration of an abnormal intracellular cholesterol trafficking is a complex procedure, and mutational analysis (NPC1 or NPC2/HE1 gene), whenever feasible, represents a major advance. Copyright © 2002 John Wiley & Sons, Ltd.     

Prenatal diagnosis of β-thalassemia in Southern Punjab,Pakistan

Pakistan has a large population of more than 150 million people with an overall carrier frequency of approximately 5.6% for β-thalassemia. Punjab is the largest province of the country having more than 50% of the population. The state of β-thalassemia is alarming as consanguinity is very high (>81%) and the literacy rate is low in South Punjab. A thalassemia prevention program is the need of the hour in this part of Pakistan. In this study, we initiated awareness, screening, and characterization of the mutations causing β-thalassemia as well as a genetic counseling program mainly in the districts of Faisalabad and D.G. Khan to establish prenatal diagnosis, a facility previously unavailable in this region for disease prevention. A total of 248 unrelated transfusion-dependent children and the available members of their families were screened to characterize the mutations and identify the carriers. Genetic counseling was provided to these families and prenatal diagnosis offered. In the samples analyzed, 11 β-thalassemia mutations and three hemoglobin variants were detected mainly by using the Monoplex and Multiplex ARMS-PCR. First-trimester prenatal diagnosis was carried out through chorionic villus sampling (CVS) in seven pregnancies at risk. As a result of our campaign, 145 carrier couples planning to have more children gave their consent to have retrospective prenatal diagnosis in every pregnancy in future. A cooperative trend and a positive attitude toward the prevention of β-thalassemia were noticed in the families with affected children and in the general population. Copyright © 2006 John Wiley & Sons, Ltd.     

田间增强UV-B辐射对麦田生态系统Fe营养和累积的影响

研究大田栽培和自然光条件下,模拟ＵＶ－Ｂ辐射（ＵＶ－Ｂ,２８０ｎｍ ～３１５ｎｍ ）增强对麦田生态系统Ｆｅ营养和累积的影响．在４ 个生育期中,ＵＶ－Ｂ辐射显著增加叶和穗Ｆｅ含量,显著降低根Ｆｅ 含量,并改变茎Ｆｅ 含量．叶Ｆｅ累积对ＵＶ－Ｂ辐射的响应有明显的生育期之间的差异． 分蘖期无显著变化,拔节期和扬花期显著增加,而成熟期显著降低．在各生育期,ＵＶ－Ｂ辐射显著降低叶、根和穗Ｆｅ累积．ＵＶ－Ｂ辐射显著降低春小麦不同生育期Ｆｅ总累积,在５．３１ｋＪ·ｍ^-2 ＵＶ－Ｂ辐射下,降低最显著．ＵＶ－Ｂ辐射还降低春小麦群体Ｆｅ输出．麦田土壤速效Ｆｅ含量增加是春小麦群体Ｆｅ输出降低的结果,可能导致土壤库中Ｆｅ 储量的增加．     

一株高效产氢突变体RF-9的筛选与产氢特性

以从连续流搅拌槽式反应器(CSTR)内的活性污泥中分离出的厌氧产氢菌Ethanologenens sp.ZGX4为出发菌株,经过紫外线和亚硝酸复合诱变,从大量的突变体中筛选出一株稳定的高效产氢菌株RF-9.磷酸盐浓度在120mmol/L、温度37℃、初始pH6.0、葡萄糖浓度10g/L培养条件下,RF-9的单位体积产氢量和氢气产率为139.7mmol/L和2.52mol H2/mol葡萄糖,分别是对照的1.50倍和1.43倍.在发酵时间为15h、pH4.1、细胞干重0.722g/L时,RF-9获得其最大产氢速率345mLH₂/(h·L),是对照ZGX4的1.41倍.RF-9的主要液相末端产物为乙醇和乙酸,为典型的乙醇发酵细菌,与对照相似.     

光助氧化技术在水处理中应用

对UV／H2O2技术、UV／O3技术、UV／O3／H2O2技术、photo—Fenton技术以及UV／TiO2技术进行了总结,对不同技术的原理、研究进展及应用进行了评述,并对今后光助氧化技术的研究方向提出了一些建议。